Focusing with the decomposition of the time reversal operator method in noisy environments

This paper presents a detailed analysis of the effects of noise （reverberation） on the focusing performance of decomposition of the time reversal operator （DORT） in a noise-limited case and in a reverberation-limited case, respectively. Quantitative results obtained from simulations and experiments are presented. The results show the DORT method can be efficiently applied to target detection with enough source level to yield significant backscatter. For a target placed on the bottom, the influence of the reverberation on the focusing performance is slight. However, distinguishing between a target and constant backscattering returning from strong local clutter on the bottom （false alarms） needs further research.